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<h1>
	                Interface Summary : IEntityResolver </h1> Basic interface for resolving entities.

 <blockquote>
 <em>This module, both source code and documentation, is in the
 Public Domain, and comes with <strong>NO WARRANTY</strong>.</em>
 </blockquote>

 <p>If a SAX application needs to implement customized handling
 for external entities, it must implement this interface and
 register an instance with the SAX driver using the
 <a href="../SAX/IXMLReader.html#setEntityResolver">setEntityResolver</a>
 method.</p>

 <p>The XML reader will then allow the application to intercept any
 external entities (including the external DTD subset and external
 parameter entities, if any) before including them.</p>

 <p>Many SAX applications will not need to implement this interface,
 but it will be especially useful for applications that build
 XML documents from databases or other specialised input sources,
 or for applications that use URI types other than URLs.</p>

 <p>The following resolver would provide the application
 with a special character stream for the entity with the system
 identifier &quot;http://www.myhost.com/today&quot;:</p>

 <pre>
 TMyResolver = class(TInterfacedObject, IEntityResolver)
 public
   function resolveEntity(const publicId,
     systemId : SAXString) : IInputSource;
 end;

 ...

 function TMyResolver.resolveEntity(const publicId,
   systemId : SAXString) : IInputSource;
 begin
   if (systemId = 'http://www.myhost.com/today') then
   begin
     // return a special input source
     FStream:= TMemoryStream.Create;
     FInputSource:= TInputSource.Create(FStream) as IInputSource;
     Result:= FInputSource;
   end else
   begin
     // use the default behaviour
     Result:= nil;
   end;
 end;

 </pre>

 <p>
      <strong>Warning:</strong>It is EXTREMELY important that the
 implementor of the IEntityResolver free the created resources.
 This can be done during the destruction of the implementing class.</p>

 <p>The application can also use this interface to redirect system
 identifiers to local URIs or to look up replacements in a catalog
 (possibly by using the public identifier).</p>

<br/><b>Since : </b> SAX 1.0
<br/><b>See : </b> <a href="../SAX/IXMLReader.html#setEntityResolver">IXMLReader.setEntityResolver</a>
<br/><b>See : </b> <a href="../SAX/TInputSource.html">TInputSource</a>
<h2>
	              Methods
	            </h2>
<div style="padding-left:10px">
<a href="#resolveEntity">
	                  function
	                 resolveEntity(SAXString, SAXString) : IInputSource</a>
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<a name="#resolveEntity">
<p>
<b>function</b> resolveEntity(<b>const</b> publicId : SAXString; <b>const</b> systemId : SAXString) : IInputSource; </p>
</a> Allow the application to resolve external entities.
 <p>The parser will call this method before opening any external
 entity except the top-level document entity.  Such entities include
 the external DTD subset and external parameter entities referenced
 within the DTD (in either case, only if the parser reads external
 parameter entities), and external general entities referenced
 within the document element (if the parser reads external general
 entities).  The application may request that the parser locate
 the entity itself, that it use an alternative URI, or that it
 use data provided by the application (as a character or byte
 input stream).</p>
 <p>Application writers can use this method to redirect external
 system identifiers to secure and/or local URIs, to look up
 public identifiers in a catalogue, or to read an entity from a
 database or other input source (including, for example, a dialog
 box).  Neither XML nor SAX specifies a preferred policy for using
 public or system IDs to resolve resources.  However, SAX specifies
 how to interpret any InputSource returned by this method, and that
 if none is returned, then the system ID will be dereferenced as
 a URL.</p>

 <p>If the system identifier is a URL, the SAX parser must
 resolve it fully before reporting it to the application.</p>

 <p>
      <strong>Warning:</strong>It is EXTREMELY important that the
 implementor of the IEntityResolver free the created resources.
 This can be done during the destruction of the implementing class.</p>

<br/><b>Parameter : </b> publicId The public identifier of the external entity
        being referenced, or empty if none was supplied.
<br/><b>Parameter : </b> systemId The system identifier of the external entity
        being referenced.
<br/><b>Result : </b> An InputSource object describing the new input source,
         or null to request that the parser open a regular
         URI connection to the system identifier.
<br/><b>Exception : </b> ESAXException Any SAX exception.
<br/><b>Exception : </b> Exception A pascal-specific IO exception,
            possibly the result of creating a new Stream
            for the InputSource.
<br/><b>See : </b> <a href="../SAX/TInputSource.html">TInputSource</a>
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